Disc-like mixing device



Nov. 17, 1964 w. L. HEARD DISC-LIKE MIXING DEVICE Filed April 8, 1963 2O 2! J5 22 p217 www PATENT AGENT United States Patent O 3,157,361 DISC-LIKE MIXING DEVICE William L. Heard, R0. Box 325, Milton, ntario, Canada Filed Apr. 8, 1963, Ser. No. 271,096 7 Claims. (Cl. 239-427) This invention relates to spraying devices.

It is frequently necessary or desirable to supply a plurality of separate liquids to a spray gun for mixture therein and spraying therefrom as a surface coating. For instance, in the spraying of polyester resins, it may be necessary to employ one solution containing an accelerator and another solution containing a catalyst.

It is an object of this invention to provide a spraying device having an improved means for mixing a plurality of liquid components prior to spraying thereof.

Another object is to provide a spraying device having effective means for mixing liquid components of a coating mixture, such means being readily accessible for cleaning or replacement.

Another object is to provide a spraying device having a spraying nozzle and a mixing means mounted therein, such nozzle and mixing means as a unit being readily insertable in and removable from a spray gun.

The invention will be described with reference to the accompanying drawing, in which FIGURE l is a sectional side elevation of a spray gun incorporating the present invention,

FIGURE 2 is a plan View of a mixing means element,

FIGURE 3 is a sectional elevation of the element shown in FIGURE 2,

FIGURE 4 is a plan View of another mixing means element, and

FIGURE 5 is a sectional side elevation of a modiiied form of nozzle portion of the spray gun,

Referring to FIGURES l to 4, is a spray gun body of generally conventional shape and having a handle portion 11 and a barrel portion 12.

A nozzle assembly 13 is removably mounted in the barrel por-tion 12 and comprises a tubular nozzle member 14 having an outwardly flared inner end section 15 terminating in a flange 16. Nozzle member 14 is disposed concentrically within a tube 17 having a web 13 through which the nozzle member 14 extends and which defines an annular air chamber 19 surrounding the nozzle member. Tube 17 has an end flange 20 whereby it, with nozzle member 14, may be fixed to the end of barrel portion 12 as by means of screw-threaded collar 21.

Air chamber 19 has an -air inlet 22 and a plurality of air outlet orifices 23 arranged about the periphery of web 1S, as well as a plurality of outlet orifices 24 arranged adjacent nozzle member 14.

Barrel portion 12 is provided with an 'axially disposed cylindrical mixing cham-ber 25 communicating at its inner end with a cylindrical valve chamber 26 and at its outer end with the interior of the flared section of nozzle member 14.

Valve-controlled means for supplying coating components to the mixing chamber 25 comprises a pair of ducts 27 and 23 communicating with chamber 25 and having respective component supply lines 29 and 30 connected thereto. A cylindrical valve body 31 is reciprocally mounted in cylinder 26 and has a passage 32 therein. It will be observed that, in the closed position of the valve body (the position shown in FIGURE l), communication of both ducts 27 and 28 with the valve chamber 26 is interrupted since the wall of body 31 overlies the outlets of the ducts. However, the valve body 31 may be moved to an open position (to the right as viewed in FIGURE l) in which duct 2S communicates with passage 32 and through the passage and valve chamber with nice mixing chamber 25, and duct 27 communicates freely with the valve chamber and the mixing chamber.

Means for reciprocating the Valve body 31 may comprise an actuating lever or trigger 33 one end of which is pivoted to the handle portion 11 at 34 and the other end of which is pivoted at 35 to a lug 36 on the end of the valve body.

Means for supplying and controlling a stream of air under pressure to the inlet 22 of air chamber 19 comprises a passage 37 in handle portion 11 to which is connected an air supply line 38 and which communicates with a valve recess 39. Recess 39 communicates with a Valve chamber 40 through an orifice 41 controlled by a poppet valve 42 normally held in closed position by a spring 43. Stem 44 of poppet 42 extends through the body portion 11 into engagement with trigger 33 whereby the spring 43 acts also to normally hold the valve body 31 in closed position, A passage 45 in the body portion 12 provides communication between valve chamber 40 and air chamber inlet 22.

It is desirable that a flow of atomizing air be initiated through the nozzle assembly just prior to the supply of liquid components to the mixing chamber 25. To this end, pivot 35 of the trigger 33 has limited sliding movement with respect to lug 36 by means of a slot 46 therein through which the pivot extends whereby initial manual movement of the trigger Will open Valve 42 and initiate the air supply before opening movement of valve body 31 which occurs following engagement of the pivot 35 with the end wall of the slot 46.

Means are provided for effecting a particularly thorough and adequate mixing of the liquid components in mixing chamber 25. To this end, a labyrinth of passages is provided in the chamber by means of a plurality (three as shown) of diametrically disposed axially spaced discs 47, 48 and 49 each having a respective tubular section Sil, 51, 52 extending axially into engagement with the adjacent disc or in the case of disc 4'7 into engagement with the end wall of the mixing chamber. Each disc has about the same diameter as the interior diameter of the chamber and the external diameter of each tubular section is considerably less than the interior diameter of the chamber. The mixing chamber is thus thereby divided into a plurality of axially aligned cylindrical zones 53, 54, 55 and a plurality of annular zones 56, 57, 58 each arranged concentrically outwardly of a cylindrical zone. As shown, zone 53 communicates directly with valve chamber 26 and with its concentric zone 56 through a plurality of circumferentially arranged openings 59 in tubular section Sti, the portion of disc 47 in zone 53 being imperforate. Zone 56 communicates with zone 57 through a plurality of circumferentially arranged openings 60 in disc 47 and zone 57 communicates with zone 54 through a plurality `of openings 61 in tubular section 51. Zone 54 communicates with zone 55 through an axial opening 62 in disc 48. Zone 55 communicates with zone 53 through a plurality of openings 63 in tubular section 52, the portion of disc 49 in zone 55 being imperforate. Zone 58 communicates with the flared interior portion of nozzle member 14 through a plurality of circumferentially arranged openings 64 in disc 49.

It will thus be apparent that flow of the liquid components is initially directed inA a plurality of streams in a radial outward direction, then in an axial direction in a plurality of streams, then in a radial inward direction in a plurality of streams, then in an axial direction in a single stream, then in radial outward direction in a plurality of streams, and finally in an axial direction into the nozzle in a plurality of streams. The result is a most thorough mixing of the two components.

In the modiiication shown, each disc 47, 48, 49 is integral or fixed to a corresponding tubular section 50, 51, 52 and may be manufactured as a separate unit, which units are, however, subject to convenient assembly into the position illustrated. Moreover, these units, as Well as the nozzle member 14, are readily removable from the gun for cleaning or replacement.

FIGURE 5 illustrates a somewhat modified form of the invention wherein the discs 47, 48, 49 with sections 50, 51, 52 are arranged within an enlarged diameter portion 65 of a tubular nozzle member 66. Nozzle member 66 has a small diameter portion 67 extending through a web 68 of tube 69. Barrel portion 70 of a spray gun body has an annular recess 71 to receive the flanged end of tube 69, as well as a concentric annular recess 72 to receive the end of nozzle member 66, the assembly being secured in position by means of a screw-threaded collar 73.

Portion 70 has an air passage 74 leading into air chamber 7S from which the air escapes around the nozzle member through a series of openings 76, a second series of openings 77 in a disc 7S carried by the web 68, a recess 79 in the web, and an annular opening 80 surrounding the outer end portion of the nozzle member.

The liquid components flow into the mixing chamber 81, constituted by the interior of the portion 65, from valve chamber 82 having control valve 83.

In this form of the invention, the liquid nozzle member, mixing chamber, and mixing means therein are incorporated in a single unit which may therefore be removed from and installed in the spray gun as a unit in a convenient manner. Should such a nozzle unit become clogged and unsuitable for re-use, it may easily be discarded and replaced with a new unit.

The nozzle member 66, and discs 47, 48, 49 with sections 50, 51, 52 may be inexpensively formed from a suitable plastic composition.

It will be observed that disc 47 with tubular section 50 is identical with disc 49 with section 52. Thus, it is contemplated that, in practice, if only two discs are ernployed in the mixing chamber, one will be a disc of one type (47 or 49) and one will be a disc of the other type (48). If more than two discs are employed, the two types will be arranged in alternate order. Thus, the desired alternate axial and radial flow patterns of the liquid components will be achieved.

I claim:

1. A spraying device comprising a spray gun body having therein a cylindrical mixing chamber and a valve chamber, a tubular nozzle member, said mixing chamber being open at one end and communicating through said open end with the interior of said nozzle member and having a side wall and an end wall at its other end, said mixing chamber having an opening in said end wall communicating with said valve chamber, and a liquid components mixing device in said mixing chamber comprising a plurality of diametrically extending axially spaced discs, a tubular section extending from each of said discs and having an external diameter less than the diameter of said mixing chamber, said discs and tubular sections forming a plurality of axially aligned liquid receiving cylindrical zones in said mixing chamber and an annular zone concentric with and radially outward of each said cylindrical zone, each said tubular section having a plurality of circumferentially arranged openings therein for radially directed liquid tiow therethrough, one of said discs having a plurality of openings therein leading from one to another of said annular zones for axially directed liquid ow therethrough, and the adjacent one of said discs having an axially directed opening therein leading from one to another of said cylindrical zones for axially directed liquid ow therethrough.

2. A spraying device as defined in claim 1, including valve means in said valve chamber for controlling supply of liquid components to said mixing chamber.

3. A spraying device as defined in claim 1, including at least three of each of said discs and tubular sections.

4. A spraying device as defined in claim 1, wherein each said disc is integral with one of said tubular sections.

5. A spraying device as defined in claim 1, said nozzle member having a tubular extension, and said mixingV chamber being disposed within said tubular extension.

6. A mixing device comprising a plurality of discs arranged to be disposed in axially aligned spaced relation, each said disc having a tubular section extending axially therefrom, said tubular section having an external diarneter less than that of said disc, each said tubular section having therein a plurality of circumferentially arranged openings, a first one of said discs having a plurality of openings therein in the portion thereof radially outwardly of said tubular section, the portion of said first disc radially inwardly of said tubular section being imperforate, and a second one of said discs having an opening therein in the portion thereof radially inwardly of said tubular section, the portion of said second disc radially outwardly of said tubular section being imperforate.

7. A mixing device as defined in claim 6, said discs being arranged in axial alignment with the tubular section of each said disc in engagement with an adjacent one of said discs, said second disc being disposed between a pair of said first discs.

References Cited in the le of this patent UNlT ED STATES PATENTS 1,122,770 Lake Dec. 29, 1914 1,260,500 Winton Mar. 26, 1918 1,826,776 Gunther Oct. 13, 1931 1,981,704 Moore Nov. 20, 1934 2,577,024 Lundberg Dec. 4, 1951 2,890,868 Potchen June 16, 1959 2,991,015 Standlick July 4, 1961 2,992,194 Paulsen Iuly 1l, 1961 3,010,658 Rutter Nov. 28, 1961 

1. A SPRAYING DEVICE COMPRISING A SPRAY GUN BODY HAVING THEREIN A CYLINDRICAL MIXING CHAMBER AND A VALVE CHAMBER, A TUBULAR NOZZLE MEMBER, SAID MIXING CHAMBER BEING OPEN AT ONE END AND COMMUNICATING THROUGH SAID OPEN END WITH THE INTERIOR OF SAID NOZZLE MEMBER AND HAVING A SIDE WALL AND AN END WALL AT ITS OTHER END, SAID MIXING CHAMBER HAVING AN OPENING IN SAID END WALL COMMUNICATING WITH SAID VALVE CHAMBER, AND A LIQUID COMPONENTS MIXING DEVICE IN SAID MIXING CHAMBER COMPRISING A PLURALITY OF DIAMETRICALLY EXTENDING AXIALLY SPACED DISCS, A TUBULAR SECTION EXTENDING FROM EACH OF SAID DISCS AND HAVING AN EXTERNAL DIAMETER LESS THAN THE DIAMETER OF SAID MIXING CHAMBER, SAID DISCS AND TUBULAR SECTIONS FORMING A PLURALITY OF AXIALLY ALIGNED LIQUID RECEIVING 